Method for obtaining fibers from at least one plant stem

ABSTRACT

A method, application and device for obtaining fibres from at least one plant stem or from plant bast is disclosed. The at least one plant stem is treated with at least one high-speed liquid jet or high-speed gas jet. At the start of treatment with the high-speed liquid jet or the high speed gas jet the at least one plant stem has a moisture content of at least 25% and/or vegetable glues, in particular the pectin and hemicelluloses, of the plant stem are in a swollen state.

BACKGROUND Technical Field

The present invention relates to a method for obtaining fibers from at least one plant stem or plant bast.

Background Information

Various methods are known from the prior art for obtaining fibers from plant stems. They are normally mechanically stripped of wood components, in part after having been biologically pre-macerated. Methods using shearing forces and others are also known. Normally, dried plant stems are used for this, which have been previously stripped of leaves. Their moisture content is 17% or less during the stripping of wood components, and is normally 14%. This is thus dealing with dried materials. Moreover, there are negative effects with the stripping of wood components, e.g. fiber damage caused by mechanical loads.

A biological pre-maceration can be carried out via a field retting or a water retting, rarely used due to its negative impact on the environment. The use of microorganisms is also known from DE 10 2006 013 657. Chemical pre-macerations are also known, e.g. from DE 11 2005 001 792 or DE 199 05 121 or WO 2006/010564 or DE 10 2007 030 576.

Flax swingles or crushing rolls are used for the stripping of wood components. The wood component is broken up into pieces thereby. A similar method is known from DE 196 26 557. It is also known to mechanically strip the ramie bast from the wood component, using blades, for example. A comparatively less effective maceration using ultrasound is also known from DE 197 03 634.

In principle, it is known to subsequently wash the obtained fibers, and to rid them of residual foreign matter. This takes place in part by spraying them with water sprayed through nozzles under pressure, as is the case in DE 197 03 634, for example.

SUMMARY

The object of the present invention is to specify an appropriate method that is superior to the conventional methods, and is suitable for obtaining fibers for further processing with less energy input and lower processing waste, even with plant stems that are difficult to break down. Special importance is given thereby to the fibers exhibiting a certain length and a certain fineness, and being able to float under certain conditions.

Thus, it is the goal of the invention in particular to obtain fibers from appropriate plant stems, which can be spun, and thus provide a corresponding yarn.

It is furthermore the object of the invention to specify a method with which a card sliver and/or card web suitable for spinning can be produced.

The objective is achieved by means of a method for obtaining plant fibers from at least one plant stem or from at least one unit of plant bast separated from wood, with or without cuticula, characterized in that the plant stem or the unit of plant bast, with or without cuticula, is broken down through treatment with at least one high-speed liquid jet or high-speed gas jet, and the at least one plant stem or the at least one unit comprising plant bast, with or without cuticula, has a moisture content of at least 25%, and/or vegetable glues, in particular pectin and hemicelluloses, of the plant stem or the unit of plant bast are in a swollen state at the start of the treatment with the high-speed liquid jet or high-speed gas jet. The objective is further achieved by an application of at least one high-speed liquid jet or high-speed gas jet for obtaining plant fibers from at least one plant stem or from at least one unit of plant bast separated from wood, with or without cuticula, characterized in that the plant stem or the unit of plant bast, with or without cuticula, is broken down through treatment with the at least one high-speed liquid jet or high-speed gas jet, and the at least one plant stem or the at least one unit comprising plant bast, with or without cuticula, has a moisture content of at least 25%, and/or vegetable glues, in particular pectin and hemicelluloses, of the plant stem or the unit of plant bast are in a swollen state before starting the treatment with the high-speed liquid jet or high-speed gas jet. The objective is still further achieved by a device for obtaining plant fibers from at least one plant stem or from at least one unit of plant bast separated from wood, with or without cuticula, characterized in that it comprises a retention and/or guide element for at least one plant stem or at least one unit comprising plant bast separated from wood, with or without cuticula, and a device for treating the at least one plant stem and/or unit comprising plant bast separated from wood received in the retention and/or guide element with at least one high-speed liquid jet or high-speed gas jet. Advantageous developments include that the plant stem or the unit, and the high-speed liquid jet or high-speed gas jet are moved in relation to one another in the direction of the longitudinal extension of the plant stem with a first speed; Furthermore, in the reference system of the plant stem, the first speed is parallel to a speed component of a second speed of the liquid or gas inside the high-speed liquid jet or high-speed gas jet. Additionally, in the method, at least one plant stem has a stem, or the unit of bast, from the group of eurosids I, in particular a hemp and/or nettle plant, and/or has a length of at least 20 cm. The method further includes that the at least one high-speed liquid jet or high-speed gas jet is generated through guiding a liquid volume subjected to at least 15 bar, in particular at least 30 bar, through a nozzle, in particular with a cross sectional tapering by a factor of 2 to 20. The at least one high-speed liquid jet or high-speed gas jet exhibits a second speed of the water in the high-speed liquid jet or high-speed gas jet, in particular at the location where it strikes the plant stem, of more than 20 m/s, in particular more than 30 m/s, in particular more than 50 m/s. Still further, the plant stem or the unit is treated with at least two high-speed liquid jets and/or high-speed gas jets, the first speeds of which form an angle of at least 60°, in particular at least 90°, in particular at least 120°, and/or the plant stem or the unit passes at least twice through the at least one high-speed liquid jet or high-speed gas jet, wherein the plant stem is rotated at least 90°, in particular at least 120° about its longitudinal axis between the passages. The plant stem may be treated on at least 180° of its circumference by the at least one high-speed liquid jet or high-speed gas jet.

Obtaining according to the invention is to be understood to mean an at least partial maceration and an at least partial separation of fibers from the remaining components.

According to the invention, the at least one plant stem or at least one unit of plant bast, with or without cuticula, is treated with a high-speed liquid jet or a high-speed gas jet, wherein the at least one plant stem or the at least one unit of plant bast, with or without cuticula, has a moisture content of at least 25%, and/or vegetable glues, in particular pectin and hemicelluloses, of the plant stem or the unit of plant bast are in a swollen state at the start of the treatment with the high-speed liquid jet or high-speed gas jet.

A unit of plant bast or a bast unit, respectively, is understood to be a coherent structure made of plant bast, which corresponds in terms of its expansion, in particular a bark region extending over a large portion, in particular to at least 30%, in particular at least 50%, of the length of the plant.

The high-speed jet (high-speed liquid jet or high-speed gas jet) produces effects thereby, in particular different, partially overlapping effects:

-   a. dissolving of water-soluble (short-chain) sugars and/or -   b. dissolving of pectins and/or -   c. suspension of pectins through hydromechanical effects and/or -   d. destruction of the cellulose/hemicellulose compounds through     hydromechanical effects and in particular, the suspension of     hemicellulose.

With respect to the dissolving of water-soluble sugars, the high-speed jet results in particular in the supplying of liquid, the solubility product of which regarding the relevant compound has not yet been obtained. In addition, there are also the effects of temperature: the solubility product increases with the heat of the solvent.

With respect to the dissolving of pectins, which takes place in particular with the use of warm/hot liquid or hot gas, in particular over 50° C., in particular over 70° C., the high speed of the liquid/gas, in particular immediately upon striking the plant material, in conjunction with the mechanical shearing and friction effects, causes the pectin to dissolve.

In the treatment with a relative speed between the high-speed jet and the longitudinal extension of the bast or the plant stem, the effect is increased, because the high-speed jet must first only achieve an initiation of the separation in the bast cylinder, and an easier continuous separation is enabled subsequently, in particular in the longitudinal direction of the plant stem or the unit, or a certain portion of the bark need not be freed of pectin in order to be peeled.

With respect to the suspension of pectin through hydromechanical effects, gel-like pectins are removed, in particular through shearing and/or friction, in particular from bark and/or fiber material, and suspended in the liquid or gas, or carried away therewith.

With respect to the destruction of the cuticula through disintegration of the united cell structure, as well as the destruction of the cellulose/hemicellulose compound through hydromechanical effects, and in particular the subsequent suspension of the cuticula, parenchyma cells, as well as the hemicellulose, the high-speed jet causes, in particular, a hydromechanical tearing of cell and fiber structures through shearing, friction and through tractive forces caused by adhesive friction. The resulting fragments of cells and fibers are suspended and can be separated from the fiber mass by means of sieves.

It is decisive thereby, that the at least one plant stem or the at least one unit of bast, with or without cuticula, have a moisture content of at least 25%, because in this state, vegetable glues, in particular pectin and hemicelluloses, are present in a swollen state, and/or vegetable glues, in particular pectin and hemicelluloses, of the plant stem or the unit of bast swell up, or are present in a swollen state, at the start of the treatment with the high-speed liquid jet or the high-speed gas jet. The advantages of the invention can only be effectively used in such a state, and a maceration, and in particular an at least partial separation, of plant fibers can take place. With comparatively little liquid and/or gas in the high-speed jet, a considerable effect can be obtained thereby. The power consumption is also low, in particular with the use of a liquid jet, because of the lower compression capacity, e.g. of water.

Moreover, there is no need to wait for the moist, pre-macerated plant stem or bast to dry, because substantial further processing steps also take place in the moist or wet state. Furthermore, the piece stripped of wood components can be substantially separated and discarded. It is furthermore possible to obtain the technical fibers composed of elementary fibers in their entire lengths, which is of particular importance with hemp and flax. In particular with hemp and ramie, it is also possible to obtain the technical fibers, or fiber bundles, in the entire length of the stem or bast, and to separate them in these lengths from the wood component.

The high-speed jet advantageously produces a separation of wood components thereby, fibers and cuticula, as well as washed out and dissolved pectins and hemicelluloses. The wood component can be obtained thereby in its entire length, and thus easily separated. The cuticula and the bark parenchyma are broken, in particular, into small pieces.

The fibers can thus be separated from the other components, in particular in the moist or wet state, by means of sieves or other separating methods.

In particular, it is preferred when all, or 80%, at least 50%, of the pectins and hemicelluloses are swollen at the start of the treatment.

A suitable state for the invention can be with fresh or green plant stems or units and/or with plant stems or units that have been pre-macerated and/or soaked in liquid, in particular water, in particular in the presence of microorganisms.

The plant stems or units are preferably subjected to a water retting or a moist or wet pre-maceration prior to the treatment, and are not dried between the water retting or the pre-maceration and the start of the treatment. A removal of the non-bonded liquid can, however, take place, e.g. by drying the surface or by wringing. The water retting or the pre-maceration can take place cold or warm.

It is furthermore preferred when the high-speed jet is directed toward the plant stem in an angular range of 30°-100°, in particular 30°-95°, between the longitudinal extension of the plant stem or the unit and the main movement direction or the direction of movement of the liquid or the gas in the high-speed jet. It is preferred thereby when the high-speed jet covers an angular range having an angular width of at least 20°, and there is an angle therein between 90° and 100° between the longitudinal extension of the plant stem or the unit, and the movement direction of the liquid.

Moreover, it is preferred when the plant stem or the unit and the high-speed liquid jet or the high-speed gas jet are moved in relation to one another at a first speed in the direction of the longitudinal extension of the plant stem or the unit.

Thus, either the plant stem or the unit of plant bast, or the high-speed liquid jet or high-speed gas jet, or both, are moved such that they are moved in relation to one another. The first speed is to be distinguished from the second speed, of the water inside the high-speed liquid jet or the high-speed gas jet. The second speed represents the high speed. The high-speed liquid jet or the high-speed gas jet is moved however with a first speed in relation to the plant stem or the unit, while the gas or liquid particles in the high-speed liquid jet or high-speed gas jet advance at a second speed inside the high-speed liquid jet or high-speed gas jet. This can occur, for example, in that the plant stem is moved in relation to the stationary high-speed liquid jet or high-speed gas jet. In particular, the relative movement or the first speed is parallel to the longitudinal extension of the plant stem or the unit of plant bast thereby. If the high-speed liquid jet or high-speed gas jet is generated, for example, by means of an appropriate nozzle, the nozzle can be stationary, for example, and the plant stem or the unit can be moved, in particular such that it is then moved toward the high-speed liquid jet or high-speed gas jet, because the high-speed liquid jet or high-speed gas jet sprays, at least in part, the length of the plant stem through the movement of the plant stem, and in particular the plant stem then exits the high-speed liquid jet or high-speed gas jet on the other side of the high-speed liquid jet or high-speed gas jet.

In particular, the first speed is parallel thereby to a speed component of the second speed, but it is not parallel, in particular, to the second speed. Parallelism is to be understood to mean orientation in the same direction thereby. Otherwise, it would be referred to as antiparallel.

Thus, the first and the second speeds overlap in part, when the water strikes the plant stem, and with an appropriate angle of incidence, a particularly effective peeling of the plant stem can be ensured.

The plant stem can be effectively peeled accordingly with such an arrangement. The cuticula and/or the wood components, in particular, are partially or entirely peeled by the high-speed liquid jet or high-speed gas jet, and in particular, the fibers are released from the bast.

With particular advantage, the at least one plant stem is a stem from the group of eurosids I, in particular a hemp and/or nettle plant. Nettle, ramie, hemp, and flax are particularly preferred. Likewise, other bast plants having a pronounced wood component can be treated successfully with the method. A pronounced wood component is understood to mean a state in which the wood component located under the bark is so stable, or physiologically old, or at a large mass ratio to the fiber component, that it does not crumble under the impact of the high-speed jet, but rather, remains intact. With plant stems from the group of eurosids I, the method can be used particularly effectively, and the fibers can be put to particularly good use. It is preferred that with hemp and nettle, a plant stem or long section thereof is used thereby. With ramie it is preferred that units of bast separated from wood are used in order to obtain a particularly good fiber quality. For lower fiber qualities of the ramie or a ramie growth of lower quality, pre-macerated intact stems are also used advantageously.

With particular advantage, the plant stems or units are not dried plant stems or units. It is further advantageous if these are young plant stems or units, in particular no older than 9 months, in particular no older than 5 months. The age does not refer to a storage period, but rather the growth period. Thus, these plants are harvested in particular at least once annually, preferably numerous times throughout the year, or at least twice, and then subjected to the method.

With particular advantage, the plant stem or the unit is a plant stem or bast unit stripped of leaves, or the method contains a step for leaf removal of the at least one plant stem or the unit prior to the high-pressure treatment and also in particular prior to a pre-maceration, if applicable, or retting. It is particularly advantageous that the plant stem or the unit is otherwise untreated.

With particular advantage, the method is a method for obtaining fibers that can be spun from at least one plant stem.

Fibers that can be spun are particularly valuable, and can be used in a wide range of applications. Thus, a yarn can be spun therefrom, and subsequently a textile material can be created.

With particular advantage, the method is carried out as a wet method, and thus, the plant stems are not dried until the moist fibers have been obtained. As a result, no dust is generated, and it is possible to macerate and separate the fibers particularly effectively. It is further advantageous when the fibers are sorted by length while wet, in particular, also processed to form a sliver while wet, stretched and/or spun.

It is preferred when the at least one high-speed liquid jet or high-speed gas jet is guided through a relative movement with the first speed in a work process over at least 40%, in particular the entirety, thus also using numerous high-speed jets or numerous treatments, over at least 70%, in particular at least 90% of the length, in particular over the entire length of the plant stem or the bast unit. With such an approach, a particularly effective peeling/opening of the plant stem or the bast unit can be obtained. However, due to the guidance for the method, e.g. due to the retaining, gripping or guidance of the plant stem, it may be difficult to reach the entire length of the plant stem in each of the at least one treatments with the at least one high-speed jet, such that lower coverage is sufficient, in particular depending on the type of plant stem and the pre-treatment.

With particular advantage, the at least one high-speed liquid jet or high-speed gas jet is generated through a water volume subjected to a pressure of at least 15 bar, particularly at least 30 bar, in particular at least 50 bar, passing through a nozzle. A higher water throughput can compensate for a lower pressure thereby, and a higher pressure can compensate for a lower water throughput. In particular, a cross sectional narrowing of the water volume, in particular by a factor of 2 to 20, can be obtained with this nozzle. As a result, a high-speed liquid jet or high-speed gas jet can be generated from a pressurized water volume. The nozzle is one, in particular, that has a clearance width of up to 2 mm, in particular 1.5 mm in at least one direction. The clearance width in one direction is preferably 0.01 mm to 0.5 mm. The shape of the nozzle can be both rectangular as well as round or oval thereby, or it can have another shape. It is particularly preferred to form a nozzle thereby that has a circular segment as the fundamental shape, and has a clearance width in the radial direction of 0.5 mm to 1.5 mm. A rotating, punctiform high-speed jet is particularly preferred. Combinations of different high-speed jets through the use of different nozzle types are particularly preferred, e.g. at least one rotational nozzle, the stream or streams of which act(s) on the plant stem or bast unit in an angular range of 30° to 95°, at least also in an angle between 70° and 95°, to the longitudinal extension of the plant stem or the bast unit, together with at least one flat-jet nozzle, the jet of which acts on the plant stem or bast unit, in particular at an angle or angular range of 10°-40° transverse to the longitudinal extension, thus at an angle or angular range of 50° to 80° to the longitudinal extension, as well as, in particular, at least one removal jet or rinsing jet of a nozzle that acts counter to the direction of movement, which is selected such that it is parallel to the longitudinal extension of the plant stem or the bast unit, and acts in particular at an angle or angular range of 10° to 30° to the longitudinal extension of the plant stem or bast unit, and in particular at an angle of 80°-100° counter to the first high-speed jet, in particular a flat-jet nozzle or rinsing nozzle.

With particular advantage, this is a high-speed liquid jet. The high-speed liquid jet particularly advantageously contains water or water vapor. Particularly advantageously, this is a high-speed water jet. The high-speed jet particularly advantageously is at a temperature of at least 40° C., in particular at least 70° C.

It is particularly preferred that a water volume of 0.1 cm³ to 4 cm³ per centimeter of plant stem is used for the high-speed liquid jet or high-speed gas jet.

It is preferred when the at least one high-speed liquid jet or high-speed gas jet exhibits a second speed of the water in the high-speed liquid jet or high-speed gas jet, in particular there where it makes contact with the plant stem, of more than 30 m per second, in particular more than 50 m per second, particularly preferred, more than 100 m per second.

The high-speed liquid jet or high-speed gas jet has an aperture angle, in particular, of less than 30° in at least spatial direction, in particular less than 10°, in particular in the direction of the radius of the plant stem. The high-speed liquid jet or high-speed gas jet has a dimension, in particular at the location where it makes contact with the plant stem, having a cross section of less than 3 mm in a direction perpendicular to the second speed, in particular less than 1 mm, in particular in the direction parallel to the radius of the plant stem. For this it is sufficient to consider the smallest cross section through which 90% of the water of the high-speed liquid jet or high-speed gas jet passes. If the cross section is curved, as preferred, the spacing of the cross sectional limits on an extended radius of the plant stem is to be regarded as the expansion in the radial direction.

A first speed is particularly preferably from 5 to 15 cm/s.

With particular advantage, and for a particularly substantial obtaining of fibers, it is preferred that at least two high-speed liquid jets or high-speed gas jets are used, and/or the at least one plant stem or the unit is treated numerous times, in particular at least twice, with the high-pressure water jet.

In the first case, the high-speed liquid jets or high-speed gas jets exhibit an angle of at least 90°, in particular at least 120° between their second speeds. Thus, the plant stem can be treated on different sides with the high-speed liquid jet or high-speed gas jet. It is also conceivable to use more than two high-speed liquid jets or high-speed gas jets. An angle of at least 90°, in particular at least 120°, must be formed here between the second speeds of at least two of these high-speed jets.

In particular, it is preferred to use three high-speed liquid jets or high-speed gas jets with an angle of 120° in each case between their second speeds, or four high-speed liquid jets or high-speed gas jets with an angle of 90° in each case between their second speeds. It is also possible to use two high-speed liquid jets or high-speed gas jets, having an angle of 180° in particular, between the second speeds.

The treatment can take place thereby simultaneously, successively, and/or with a temporal overlap. It can also take place thereby at the same position in the longitudinal direction of the plant stem, but at different points on the circumference. It is preferred however, to carry out the treatment at slightly offset points in the longitudinal direction, in particular offset by 1 mm to 15 mm in the longitudinal direction, such that they overlap in a temporal manner. The temporal overlap is selected to be a large as possible thereby. In particular, it is preferred that the high-speed liquid jets or high-speed gas jets are oriented such that they treat a plant stem guided past them at the specified spacings, and the treatment takes place in each case while the plant stem passes through the respective high-speed liquid jet or high-speed gas jet.

In the second design, the plant stem is treated numerous times by the same high-speed liquid jet or high-speed gas jet, and rotated about its longitudinal axis between these treatments. A rotation of at least 90°, in particular 120°, is preferred thereby. If more than two passages take place, the overall rotation must amount to the same angular total thereby. Thus, it is preferred that a rotation of 180° be carried out with a double passage, 120° with a triple passage, 90° with a quadruple passage, etc. In this manner, the stem is rotated a total of 360°.

Particularly advantageously, the plant stem is treated on a minimum of 180° of its circumference with the at least one high-speed liquid jet or high-speed gas jet. This can be achieved through different segments over the curvature, which amount to a total of 180°, or on a coherent curve segment, thus a half-circle segment. It is preferred however that it be divided into numerous segments that total to at least 180°. Thus, it is preferred, for example, that at least three or four segments are provided, which form a combined total of 180°, and in particular are distributed evenly, and each disposed such that they cover a curve segment having the same size.

For a particularly complete obtaining of fibers and pure fibers, a covering of the circumference of the plant stem over at least 270° is preferred, however.

It is particularly preferred when the plant stem or the unit is retained and/or guided at least temporarily during the treatment with the at least one high-speed liquid jet or high-speed gas jet, in particular during the entire time of the treatment with the at least one high-speed liquid jet or high-speed gas jet. It has proven to be particularly advantageous thereby to guide and/or retain the at least one plant stem or unit individually, or to provide a spacing, in particular transverse to the longitudinal extension of the plant stems or units, between numerous retained plant stems or units. In particular, a retention and/or guidance from at least two sides, and in particular a securing in all three spatial axes, e.g. by pressing them from both sides between two grids and/or sieves, is preferred.

A guidance or retention, whether individually or in bunches, can be obtained, for example, by means of grippers, lateral boundaries, clamping, e.g. between numerous conveyors, or via rollers.

Thus, a stem can be grasped by a gripper and subjected to the treatment. It is also conceivable that a plant stem is retained and guided by two or more rollers, in particular it is transported in its longitudinal direction and subjected to the treatment thereby. Thus, two or three rollers can be used, for example, which are disposed such that they can convey a plant stem placed between them by rotating the rollers. The rollers are advantageous pressed against the plant stems thereby, and thus retain it securely. The first speed, or a portion of the first speed can be obtained through the movement of the rollers or the gripper, or the conveyor. It is also possible to place plant stems in appropriate boundaries, in particular lateral boundary elements. In this manner, numerous parallel rises can form corresponding grooves, in which the plant stems are placed. These can also be pressed, entirely or in part, in particular laterally, against the plant stem in order to retain it. These grooves can also have further boundaries, which run perpendicular to the grooves, for example, and prevent a slipping of the plant stems in the direction of the grooves. The plant stems can also be pressed down by appropriate pressure means that act on plant stems placed on a pad, thus securing numerous plant stems on a surface. This surface or pad can also be a conveyor belt, on which the plant stems are pressed and secured, and can be conveyed. A securing or a retaining can take place by means of elongated elements, for example, such as bars, rods, or tubes, which are pressed onto the plant stems transverse to the longitudinal extensions thereof. These exhibit an expansion of less than 50 mm, in particular less than 10 mm, in the direction of the longitudinal extension of the plant stem, in particular. It is also possible to provide smaller pressure elements, having an L or U shape, for example, and to thus press the plant stems individually onto a surface, and to retain them accordingly. This surface can in turn be a conveyor element. It is also possible to obtain a clamping of the plant stem through pressure exerted by conveyors or retention means such as grids or sieves, from two sides, e.g. by means of conveyor belts having, in particular, recesses. If numerous plant stems or units are retained, gripped, guided and/or transported during the treatment with the at least one high-speed jet, then these plant stems are aligned in a common longitudinal direction, before they are retained or secured accordingly.

Thus, with particular advantage, numerous plant stems or units arranged in parallel, in particular on a conveyor belt, in particular retained thereon, can be treated, in particular simultaneously, with the at least one high-speed liquid jet or high-speed gas jet.

In one design, it is preferred that each plant stem or each bast unit be gripped and/or guided individually. A guidance via appropriate rollers, for example, is preferred here.

There is no reason not to guide numerous plant stems individually at the same time, and to treat them simultaneously with at least one high-speed liquid jet or high-speed gas jet.

Particularly advantageously, an adequate removal of the liquid or gas supplied by the high-speed jet is provided for. This is adequate, in particular, when the liquid or gas does not back up, such that the plant stems or the units and/or the components thereof, float, or are entirely encompassed, and/or the high-speed jet is substantially slowed and/or affected.

This can take place, for example, by providing sieves or grids as the supporting surfaces and/or retention means, or through freely guiding the stems or the units at the location of the high-speed jet treatment. Preferably, with the treatment of numerous adjacent and/or stacked plant stems or units, a minimum layer thickness, in particular a single layer, and in particular a spacing between the plant stems or units, is provided. It is particularly preferable that a vacuum be applied beneath the specified sieves by means of appropriate devices, in order to facilitate the removal of the liquid via gravity.

It is particularly preferred, in particular with the processing of nettles, to provide a removal or rinsing jet, in particular a removal liquid jet or removal gas jet, and/or flow, in particular likewise in the form of a high-speed jet, which removes the components of the plant stems dissolved and/or released in the bark. These removal jets or these removal flows are oriented thereby in a direction that is aligned with the longitudinal extension of the plant stems, or forms an angle of −25° to 25°, preferably −10° to +10°. These removal jets or removal flows are at an angle to a high-speed jet, in particular, of 40° to 90°. In particular, the plant stem or the bast unit is moved parallel to the longitudinal extension and counter to the removal or rinsing jet and/or a removal or rinsing flow.

The method particularly advantageously contains a pre-maceration of the plant stem prior to the treatment with the at least one high-speed liquid jet or high-speed gas jet, and/or a post-maceration, in particular with the use, in particular exclusively, of pectinases and/or hemicelluloses as such, or of microorganisms forming these, and/or a washing of the treated fibers. A pre-maceration can be carried out, for example, by means of a water retting and/or a soaking in water.

A washing advantageously takes place at at least 50° C., in particular at least 60° C., with water, while optionally adding further components, e.g. soapwort abstract. In another design, it is preferred that only water be used for the washing.

Particularly advantageously, a sorting of the obtained fibers into different lengths takes place after the treatment with the high-speed liquid jet or high-speed gas jet, after the post-maceration, and/or after the washing. This can be achieved in a variety of ways. A sorting is conceivable, for example, through gravity in an appropriate bath, or in a bath in which gas is blown in at the base, which cause the fibers to float at different heights in the bath, depending on their lengths. Nitrogen or carbon dioxide can be blown in here. The blowing in of air is also conceivable. The fibers sorted by elevation are then skimmed off accordingly.

It is also possible to obtain a sorting with needle boards or needle conveyors. Thus, one or more moving conveyors can be provided, equipped with needles or thin elongated elements, pointing upward, in particular at a diagonal, in particular at an angle of 30°-70° in relation to horizontal, which are rinsed with a liquid flowing in a direction counter to the conveyance direction, and in particular out of a bath containing the fibers. Depending on the rinsing strengths, conveyance slope and the diameter of the elongated thin elements, there are different affinities of the various fibers, despite the counter-rinsing, to remain on the elongated thin elements, and to thus be transported. As a result, with different diameters of the elongated thin elements, different fiber lengths can be removed from a bath. Longer fibers are removed first thereby, in particular in a temporal manner or with respect to the flow path of the fibers, and fibers with successively shorter lengths are removed by elongated elements having smaller diameters. The longitudinal axes of the thin elongated elements are oriented perpendicular to the direction of conveyance thereby, or exhibit an angle thereto of at least 60° and no more than 120°.

Particularly advantageously, the water used in the various steps of pre-maceration, high-speed liquid jet or high-speed gas jet, post maceration, and washing or sorting, is reused, this being such that water from the downstream steps, if necessary after appropriate processing, such as filtering, is used again in the upstream steps for other plant stems. The water used for peeling by the high-speed liquid jet or high-speed gas jet is sieved or, optionally, filtered, in particular. It is also conceivable to provide a drum, inside which the treatment with the high-speed liquid jet or high-speed gas jet takes place, and which rotates, in particular, about the longitudinal extension of the plant stem, and which is used for collecting bark components. This drum can be subjected to a vacuum, for example, in order to collect and retain the released bark components, and to unload the drum, for example, the vacuum can be removed and/or the drum can be subjected to an overpressure, in particular in a section of the circumference provided for this, through which the drum rotates, in order to remove the components retained on the drum.

In particular, the obtained, in particular, washed, fibers are boiled and/or bleached.

The method particularly advantageously has a step for generating biogas. This is first generated by the normally present population of microorganisms in the containers sealed against the atmosphere for pre- and/or post-maceration. In addition, the biogas generation is promoted, in particular, through the use of the liquid or gas for the high-speed liquid jet or high-speed gas jet, or the biomasses dissolved and/or suspended therein, and the introduction thereof into the pre- and/or post-maceration containers. It is also possible to use the substances obtained during filtering in the course of the water processing for obtaining biogas. Solids that are likewise obtained, for example, on the filters for the water processing or during the peeling, or are already obtained during the de-leafing, can likewise be used for obtaining biogas. They can also be dried, however, and pressed into pellets, in particular, to be used as fuel, fodder, or fertilizer.

As a result, the method obtains a particularly positive energy/ecology balance.

The objective is achieved by the use of at least one high-speed liquid jet or high-speed gas jet for obtaining plant fibers from at least one plant stem or from at least one unit of plant bast separated from wood, with or without cuticula, characterized in that the plant stem or the unit of plant bast, with or without cuticula, is broken down through treatment with the at least one high-speed liquid jet or high-speed gas jet, and the at least one plant stem or the at least one unit comprising plant bast, with or without cuticula, has a moisture content of at least 25%, and/or vegetable glues, in particular pectin and hemicelluloses, of the plant stem or the unit of plant bast are in a swollen state at the start of the treatment with the high-speed liquid jet or high-speed gas jet. The features and advantages specified with respect to the method can be transferred accordingly thereby.

The objective is achieved as well through a device for obtaining plant fibers from at least one plant stem or from at least one unit of plant bast separated from wood, with or without cuticula, characterized in that a retention and/or guidance is provided for at least one plant stem or at least one unit separated from wood, comprising plant bast with or without cuticula, and a device is provided for treating at least one plant stem and/or unit separated from wood, comprising plant bast, received in the retention element and/or guide element with at least one high-speed liquid jet or high-speed gas jet.

The device is configured thereby for executing a method according to the invention in particular. The features specified with respect to the method can also be transferred to the device, in particular by providing appropriate devices for generating a high-speed jet, a removal jet or removal current, and/or for retention and/or guidance of the stem or the unit through devices, in particular baths for pre-maceration and/or retting, and in particular a means for the transportation thereof to the high-speed treatment.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Further advantages and advantageous designs shall be described by way of example on the basis of the schematic Figures. Therein:

FIG. 1: shows a state of the manual labor for implementing the method according to the invention, and

FIG. 2: shows an assembly for implementing the method according to the invention on numerous plant stems placed at spacings to one another;

FIG. 3: shows a treatment strategy for executing the method according to the invention.

DETAILED DESCRIPTION

A U-profile 1 can be seen in FIG. 1, having a slot-shaped opening in the lower region. A flat-jet nozzle 4 is disposed in this opening, disposed such that its high-speed water jet is disposed with its width parallel to the base of the U-profile, and with its jet direction forming an angle of 10° to the longitudinal direction of a straight plant stem 2 placed in the U-profile 1 in the longitudinal direction.

Another nozzle 5 can also be seen therein, which generates a rotating high-speed water jet, which covers an angular range of 30° to 95° to the longitudinal extension of the inserted plant stem 2 with its jet direction.

Moreover, a third nozzle 6 can also be seen therein, which generates a flat-jet high-speed water jet, which forms an angle of 75° to the longitudinal extension of the inserted plant stem 2 with its jet direction, and is disposed with its width parallel to the first flat jet.

The plant stem 2 can be placed in the U-profile 1 by a user, and pulled upward and to the left. The jets of the upper nozzle release bark, together with fibers thereby. The jet from the lower nozzle 3 supports the removal of the removed and/or released components. In order to remove these components and the water, the longitudinal extension of the U-profile 1 is tilted in relation to the horizontal plane.

The user can thus guide the plant stem 2 back downward and toward the right, and rotate it, and pull it back upward and toward the right, to peel again, in particular on another side.

Alternatively and/or subsequently, the user can turn the plant stem 2 over and peel it as described above on the side that was not previously treated.

FIG. 2 shows a top view of a sieve 7, on which plant stems 9 are placed, substantially parallel to one another and spaced apart, which are retained with a bar 8 pressed thereon. Furthermore, two flat-jet nozzles 10 can be seen, each of which emits a wide high-speed water jet, and is moved by the bar 8 from the inside toward the outside. In this manner, they peel the plant stem 2. The water can escape through the sieve 7. Depending on the design of the sieve 7, the removed material can escape through the sieve 7, either entirely or in part. Otherwise, it can be removed from the sieve 7 in another step, in particular separately from the remaining stems.

The securing of the plant stems 9 spaced apart from one another ensures that the plant stems 9 do not overlap, and cannot evade the high-speed water jet.

The remaining stems can be subsequently clamped at another location, and again processed for peeling with a high-speed water jet, in particular at the location of the first clamping.

Subsequently, and/or alternatively, the stems can be used and reprocessed again from another side for peeling with one or more high-speed water jets, in particular as described above.

Particularly advantageously, the fibers obtained with this invention are treated immediately with the subsequent method, which is also an independent invention, and can be implemented independently, for example, with fibers or fiber slivers obtained by other means, or following other treatments, such as washing, sorting, e.g. according to fiber lengths, cleaning, bleaching, dying and/or sliver formation.

In principle, it is also known to subsequently wash the obtained fibers, and to rid them of foreign components. This takes place in part through subjecting them to water forced through the nozzles under pressure, as is disclosed, for example, in DE 197 03 634.

It is also known to comb the fibers, and to likewise clean them as a result. It is likewise known to double and/or stretch the fibers. This takes place when they are dry, and normally after the fibers have been processed to form a card sliver or card web, or comb sliver. It is also known to boil and/or bleach the fibers, in particular in the form of a sliver, and to further clean and bleach them thereby, e.g. through an appropriate flow in a kettle for example.

The drawing and spinning is limited by the properties of the ratio of the length to the width of the technical fibers, defined by the technical fibers. Furthermore, the machines used for combing also consume a comparably large amount of energy. Moreover, significant energy is used for an optional upstream drying.

The object of the further invention is to define a corresponding method, which is superior to the conventional method, and enables a superior cleaning with the lowest possible energy consumption, and/or enables the ratio between the length and thickness of the technical fibers to be increased.

Thus, it is the goal of the method, in particular, to obtain fibers from appropriate plant fibers, which are cleaned and can be spun, in order to thus create a yarn therefrom. In particular, the ratio of the length to the thickness of the technical fibers is also increased thereby.

This object is achieved by a method, an application, and a device.

According to this further invention, plant fibers are treated with at least one high-speed liquid jet or high-speed gas jet, and subsequently processed while wet, in particular cleaned, refined and/or oriented.

The high-speed jet (high-speed liquid jet or high-speed gas jet) produces various effects thereby, in particular partially overlapping effects:

-   a. dissolving of water soluble (short chain) sugars and/or -   b. dissolving of pectins and/or -   c. suspension of pectins through hydromechanical effects and/or -   d. destruction of cellulose/hemicellulose compounds through     hydromechanical effects, and in particular the suspension of     hemicellulose. -   e. rinsing out of contaminants

With respect to the dissolving of water soluble sugar, the high-speed jet results, in particular, in the supplying of liquid, the solubility product of which has not yet been obtained with respect to the relevant compound. In addition, there are also the effects of temperature: a warmer solvent results in a higher solubility product.

With respect to the dissolving of pectins, which occurs in particular when warm/hot liquid or hot gas is used, in particular over 50° C., in particular over 70° C., the dissolving of pectin is caused by the high speed of the liquid/gas, in particular immediately after striking the plant material, in conjunction with the mechanical shearing and friction effects.

With the treatment with a relative speed of the high-speed jet to the longitudinal extension of the plant fibers and/or the sliver in which the fibers are present, and/or the direction of transport for the plant fibers and/or the sliver in which the fibers are present, the effect is increased, because the high-speed jet must first only achieve a starting of the separation, and subsequently, in the further course, in particular in the longitudinal direction of the plant fibers, enables an easier continuing separation, or a certain portion does not have to be freed of pectin in order to be separated and/or released.

With respect to the suspension of pectins through hydromechanical effects, gel-like pectins are driven out in particular through shearing and/or friction, and suspended in the liquid or gas, or carried along therewith.

With respect to the destruction of the cuticula through disintegration of the cell bond, as well as the destruction of the cellulose/hemicellulose compound through hydromechanical effects, and in particular the subsequent suspension of the cuticula as well as the hemicellulose, the high-speed jet causes, in particular, hydromechanical tearing of cell and fiber structures through shearing, friction, and tractive forces caused by adhesive friction. The fragments of cells and fibers resulting thereby are suspended and can be separated from the fiber mass.

The technical fibers formed by elementary fibers can be partially macerated through such effects, and a modification of the properties of the technical fibers can be produced, such that the ratio of its length to its thickness is increased, in that its specific surface area increases, and in particular its quantity is increased.

Not only can released contaminants be effectively and efficiently removed through the processing, e.g. combing or treatment with a further high-speed jet while wet, but also a positive modification of the geometrical properties of the technical fibers can be implemented in a pronounced manner, in particular when stretching forces are applied, e.g. combing, during the processing.

The plant fibers are, in particular, already macerated plant fibers, and/or plant fibers that are substantially separated from and/or freed of wood components and/or other contaminants such as bark components. They are already freed thereby of, in particular, at least 40%, in particular at least 70%, of the original contaminants or foreign bodies in the plant stem, such as wood components or bark components. In particular, they contain a maximum of 20% by weight of contaminants or foreign bodies, such as woody components or bark components.

The plant fibers are obtained thereby in particular at least in part, in particular in their entirety, from plants in the group of eurosids I, in particular from hemp and/or nettle plants, particularly preferably nettles, ramie, hemp, flax, jute and kenaf.

In particular, the processing takes place through combing, in particular the cleaning, orienting and/or refining, when wet, immediately after the treatment with the at least one high-speed jet, at least within a maximum of 48 hours.

The processing, in particular the cleaning, orienting and/or refining, is carried out in particular through combing, such that a stretching of the plant fibers primarily takes place, in particular in the form of a card sliver, card web, or comb sliver. This is achieved in particular through the clamping and transporting of the fibers between two rotating rollers, and the subsequent combing, wherein the speed of the devices for combing and or their combs deviates from the conveyance speed through the rotating rollers, and is specifically higher.

The device for combing can be formed in particular by rotating rollers, which are populated with nails, needles, pins, rods and/or rakes, and are disposed such, and rotate with such a speed, that the nails, needles, pins, rods and/or rakes comb through the plant fibers, in particular in the form of a sliver. The circumferential speed of the populated rollers is selected thereby such that it differs from that of the rotating and clamping rollers disposed upstream in the transport.

By providing numerous such combinations of clamping and populated rollers, also known as carders, in a series, the transport speed, in particular from one to the next carder is increased, and as a result a (further) stretching is obtained.

This is advantageous in particular when a treatment with at least one high-speed jet takes place between the carders, in which the technical fibers are partially loosened and/or macerated and/or their length to thickness ratio is increased. As a result of the stretching, an increase in the length to thickness ratio can take place in the partially loosened and/or macerated fibers, and/or the increase in this ratio can be used for the stretching.

Particularly advantageously, the plant fibers have a moisture content of at least 25%, in particular at least 40%, prior to the treatment with the at least one high-speed jet, because in this state, vegetable glues, in particular pectin and hemicelluloses are in a swollen state, and/or vegetable glues, in particular pectin and hemicelluloses, of the plant fibers are swollen or have swelled. This can also be obtained when excessively moist plant fibers, e.g. those having a high proportion of retained water, are freed of such retained water shortly or immediately prior to the treatment, particularly on the surface, e.g. by wringing. As a result, the moisture is reduced, but moisture is not substantially removed from the vegetable glues. The drying must be designed such that there are still swollen vegetable glues present thereafter. The advantages of the invention can be used effectively in particular in such a moist and/or swollen state, and a maceration and in particular an at least partial separation of plant fibers can take place particularly effectively and efficiently. A considerable effect can be achieved thereby with comparatively little liquid and/or gas in the high-speed jet. The energy consumption is also low, in particular with the use of a liquid jet.

In particular when the obtaining of plant fibers from stems takes place in a moist state, there is no need for an intermediate drying, e.g. following a moist pre-maceration or a water retting.

In particular, it is preferred when all or 80%, at least 50% of the pectins and hemicelluloses are in a swollen state at the start of the treatment.

A particularly suitable state for the invention may be present in particular in plant fibers obtained from fresh or green plant stems that have not been dried, and/or plant fibers that have been pre-macerated and/or soaked in liquid, in particular water, in particular in the presence of microorganisms.

Preferably, the plant fibers are subjected to a water retting or a moist or wet pre-maceration prior to the treatment, in particular after the removal woody components and in particular after a first cleaning, and not dried between the water retting or the pre-maceration and the start of the treatment, in particular, they are not dried to the extent that the vegetable glues become significantly less swollen, in particular no more than 50%. A removal of the liquid not bonded in the vegetable glues can however take place, e.g. through squeezing. The water retting or the pre-maceration can take place cold or warm.

The high-speed liquid jet or high-speed gas jet preferably has a speed of the liquid or gas in the high-speed liquid jet or high-speed gas jet, in particular at the location of contact with the plant fibers, of more than 20 m/s, in particular more than 30 m/s, in particular more than 50 m/s.

The at least one high-speed liquid jet or high-speed gas jet is particularly advantageously generated by the passage of a water volume subjected to a pressure of at least 15 bar, in particular at least 30 bar, in particular at least 50 bar, through a nozzle. In this manner, a high water throughput can compensate for a low pressure, and a high pressure can compensate for a low water throughput. A cross sectional tapering of the liquid volume is achieved through this nozzle, in particular by a factor of 2 to 20. As a result, a high-speed liquid jet or high-speed gas jet can be generated from a pressurized liquid volume. The nozzle is such a nozzle that has a clearance width in at least one direction of up to 2 mm, in particular 1.5 mm. The clearance width in one direction is preferably 0.01 mm to 0.5 mm. The shape of the nozzle can be rectangular as well as round or oval thereby, or it can take another shape. It is particularly preferable thereby to form a nozzle, for example, that has a circular segment as the fundamental shape, and has a clearance width in the radial direction of 0.5 mm to 1.5 mm. A rotating punctiform water jet is particularly preferred. Combinations of various nozzle types are particularly preferred, e.g. the nozzle acting basically perpendicular to the fiber sliver or the bast unit, e.g. at an angle of 70° to 100°, in particular a rotational nozzle, together with a nozzle that sprays at an angle of 20°-40° transverse to the direction of movement of the plant stem, but is directed in the direction of movement of the fiber sliver or the bast unit, in particular a flat-jet nozzle.

This is particularly advantageously a high-speed liquid jet. The high-speed liquid jet particularly advantageously contains water or water vapor. It is particularly advantageously a high-speed water jet. The high-speed water jet particularly advantageously is at a temperature of at least 40° C., in particular at least 70° C.

Particularly preferably, a quantity of liquid or gas of 10 cm³ to 30 cm³ per gram of plant fiber or contaminated plant fiber is used as the high-speed liquid jet or high-speed gas jet.

It is preferred when the at least one high-speed liquid jet or high-speed gas jet has a second speed of the liquid or gas in the high-speed liquid jet or high-speed gas jet, in particular at the location of contact with the plant fibers, of more than 30 m/s, in particular more than 50 m/s, preferably more than 100 m/s.

The high speed liquid jet or high-speed gas jet has an aperture angle of less than 30° in at least one spatial direction, in particular less than 10°, in particular in the direction of the radius of the fibers or the fiber sliver. The high-speed liquid jet or high-speed gas jet has, in particular at the location of contact with the plant fibers, a cross sectional size of less than 3 mm, in particular less than 1 mm, at least in one direction perpendicular to the speed of the liquid or gas in the jet. It is sufficient for this to consider the smallest cross section through which 90% of the liquid or gas of the high-speed liquid jet or high-speed gas jet will pass. A punctiform high-speed water or high-speed gas jet rotating about the central axis, having a high rotational frequency, e.g. of 80 rotations per second, can be used with particular advantage.

The plant fibers are parallelized, particularly advantageously prior to, after and/or during, in particular prior to, the treatment with the at least one high-speed jet, or they are parallel during the treatment and/or in a card sliver or card web.

The parallelization takes place thereby, in particular with the use of at least one alignment high-speed jet, for which the features specified in particular with respect to the at least one high-speed jet apply. This can take place, for example, through a driving of the fibers with the at least one alignment high-speed jet, in particular uphill, or in/over a region in which the liquid and/or gas removal is reduced with respect to the region from which they are driven.

Particularly advantageously, the liquid removal or gas/liquid removal is caused in that a vacuum is applied to a sieve located in a region where the high-speed jet strikes the plants on the side of the fibers or the sliver lying opposite the source of the high-speed jet, which vacuum is advantageously modulated over time.

Moreover, the provision of a trough intake is preferred, in particular in the form of a trough and a gripping roller therein, which guides the fibers clamped between the trough and the roller, and a device for pulling the fibers out of the trough and/or for guiding them away from the trough and/or roller, and for the uniform presentation of the plant fibers and for (further) parallelization, in particular after a parallelization by means of the alignment high-speed jet. As a result, a uniform presentation, preferred per se, can be obtained.

The plant fibers are particularly advantageously treated numerous times with the high-speed liquid jet or high-speed gas jet, and subsequently, in particular each time, combed while moist. In particular, the plant fibers are treated from at least two sides with at least one high-speed liquid jet or high-speed gas jet, and subsequently, in particular each time, combed while moist. The combing takes place thereby, in particular, from different sides.

In general, it is preferred, in particular with just single and/or one-sided treatment with a high-speed jet, when the moist fibers are treated with the at least one high-speed jet in a layer having a layer thickness of less than 20 mm, in particular less than 10 mm. In a special process, the plant fibers are stretched and/or doubled while moist. The stretching advantageously takes place thereby, at least in part, through combing.

Advantageously, the liquid of the at least one high-speed jet or high-speed gas jet is removed such that there is no liquid back-up that compromises the high-speed liquid jet or the high-speed gas jet, or that lays the plant fibers in a liquid bed, or that allows the plant fibers to float. This can take place with an appropriate drainage possibility, for example, by laying the plant fibers on a grid and/or sieve and/or a sufficiently thin and/or loose arrangement of the plant fibers during the treatment with the at least one high-speed jet. It is particularly preferred that a vacuum be applied beneath the aforementioned sieve/grid, which actively draws off the liquid.

The plant fibers are contained with particular advantage in a card sliver or card web, treated with the at least one high-speed liquid jet or high-speed gas jet, and subsequently combed while moist. In this form, a guidance and further processing is particularly efficient.

It is furthermore preferred when the high-speed jet is directed toward the plant fibers at an angle of 30°-70°, in particular 40°-60°, between the longitudinal extension of the plant fibers and/or the sliver containing the fibers, and/or the direction of transport for the plant fibers and/or the sliver containing the fibers.

It is particularly preferred when the plant fibers and the high-speed liquid jet or high-speed gas jet are moved at a first speed in relation to one another in the direction of the longitudinal extension of the plant fibers and/or the sliver containing the fibers, and/or in the direction of transport for the plant fibers and/or the sliver containing the fibers.

It is particularly preferred that a flat jet be used as the high-speed jet, which extends, for example, over the entire width of the fiber sliver, or fibers, respectively. The nozzle forming the high-speed jet is moved back and forth, in particular at a higher speed than the conveyance speed of the fibers, parallel thereto, although the high-speed jet is only directed toward the fibers or the fiber sliver, or generated for this, in the time windows in which the speeds of the nozzle and the conveyor overlap in a positive manner, to obtain a high relative speed.

Thus, either the plant fibers and/or the sliver containing the fibers, or the high-speed liquid jet or high-speed gas jet, or both, are moved such that they are moved in relation to one another. The second speed of the liquid and/or gas inside the high-speed liquid jet or high-speed gas jet is to be distinguished from the first speed. The second speed represents the high speed. The high-speed liquid jet or high-speed gas jet itself, however, is moved at a first speed in relation to the plant fibers and/or the sliver containing the fibers, while the gas or liquid particles in the high-speed liquid jet or high-speed gas jet move at a second speed inside the high-speed liquid jet or high-speed gas jet. This can occur, for example, in that the plant fibers and/or the sliver containing the fibers, are moved in relation to the stationary per se high-speed liquid jet or high-speed gas jet. The relative movement, or the first speed, is that which is parallel to the longitudinal extension, in particular, of the plant fibers and/or the sliver containing the plant fibers, and/or the direction of transport for the plant fibers and/or the sliver containing the fibers. If the high-speed liquid jet or high-speed gas jet is generated, for example, by an appropriate nozzle, the nozzle can be stationary, for example, and the plant fibers and/or the sliver containing the plant fibers can be moved, in particular such that they/it are/is first moved toward the high-speed liquid jet or high-speed gas jet, then the high-speed liquid jet or high-speed gas jet is sprayed, at least in part, over the length of the plant fibers and/or the sliver containing the fibers by moving the plant fibers and/or the sliver containing the fibers, and in particular, the plant fibers and/or the sliver containing the plant fibers then exits the high-speed liquid jet or high-speed gas jet on the other side of the high-speed liquid jet or high-speed gas jet.

The first speed is parallel, in particular, to a speed component of the second speed thereby, but not parallel, or antiparallel to the second speed, in particular. Parallelism is understood thereby to be an orientation in the same direction. A reversed orientation would be referred to as antiparallel here.

Thus, the first and second speeds overlap in part, such that when the liquid or gas strikes the plant fibers and/or sliver containing the fibers, there is a lower relative speed than the total of the two speeds. As a result, an increase in the ratio of the length to the thickness and/or a stretching is supported and/or produced.

In another design, in particular when the plant fibers are not in the form of a sliver, and/or when the plant fibers are present individually or as a bunch or a bundle, it is preferred to carry out the treatment with the at least one high-speed jet in a rotating drum that conveys the fibers. In this case, an alignment of the at least one high-speed jet such that it reduces the conveyance speed is preferred, i.e. an alignment such that it is at least partially counter to the conveyance speed, in particular.

With a treatment in a conveying drum sieve, it is possible for the fibers to rotate and turn when they fall down during the upward transport. Consequently, it is possible to treat the fibers in a uniform manner and on all sides, in particular when numerous, or at least one, wide, high-speed jets are provided for the treating of a single, or numerous successive rotating and conveying drum sieves, likewise each equipped with at least one high-speed jet.

It is also preferred, in particular when the plant fibers are not in the form of a sliver and/or when the plant fibers are present individually or as a bunch or bundle, to carry out a treatment with the at least one high-speed jet while the fibers are disposed in an elongated trough. This can be formed, in particular, by an elongated sieve or grid, which is curved transverse to the longitudinal extension, in particular having a semicircle cross section. It is preferred in particular to treat the plant fibers while they are placed such that a widening of the fibers in at least one spatial direction, in particular, is reduced and/or prevented. It is preferred thereby, when there is a tendency to slide together in at least one spatial direction as a result of the placement thereof. The use of at least one rotating high-speed jet is preferred thereby, in particular, as is generally the case with the generation of a plant fiber sliver using a high-speed jet, by means of which the formation of the sliver is promoted.

The formation of a plant fiber sliver by the at least one high-speed jet can be effected through such a process. This sliver can then be combed while moist. Advantageously, however, the sliver is first treated with at least one further high-speed jet, and subsequently, and/or after each treatment with a high-speed jet, combed, and in particular stretched, while moist.

The plant fibers are particularly advantageously boiled and/or bleached after the treatment with at least one high-speed jet, and in particular after the stretching, in particular while subjecting the plant fibers to a liquid flow for further rinsing out, in particular, of released and/or suspended contaminants.

The object is also achieved through the use of at least one high-speed liquid jet or high-speed gas jet for cleaning and/or for increasing the ratio of fiber length to fiber thickness of plant fibers. The plant fibers are treated thereby with at least one high-speed liquid jet or high-speed gas jet, and subsequently combed while moist. The aspects and advantageous features specified with respect to the method can be transferred accordingly.

The object is also achieved by a device for cleaning and/or for increasing the ratio of fiber length to fiber thickness of the plant fibers. At least one guide and/or retention element for plant fibers, and a device for treating the plant fibers guided and/or retained with the guide and/or retention element with at least one high-speed liquid jet or high-speed gas jet, as well as at least one device for combing the plant fibers while moist, are provided thereby. In particular, the device is configured for executing a method according to the invention, in particular through the provision of the appropriate means, and/or in particular a control, for executing the method according to the invention. The device for combing while moist is a carder, in particular. In particular, the device has numerous devices for treating the plant fibers retained and/or guided with the at least one guide and/or retention element with at least one high-speed liquid jet or high-speed gas jet, as well as numerous devices for combing the plant fibers while moist. At least one guide and/or transport device is provided thereby, which is configured to transport the fibers from a first device for treating the plant fibers retained and/or guided with the at least one guide and/or retention element with at least one high-speed liquid jet or high-speed gas jet, to a first device for combing the plant fibers while moist, and in particular to at least one further device for treating the plant fibers retained and/or guided with the at least one guide and/or retention element with at least one high-speed liquid jet or high-speed gas jet, and, in particular subsequently, to at least one further device, in particular, for combing the plant fibers while moist.

In particular, the transport speed is increased thereby at the end, thus obtaining a stretching. In particular, the transport device is a component of, or contains, the at least one guide and/or retention element.

The transport device, guide and/or retention element, is configured thereby to transport the fibers, in particular in the form of a card sliver or card web, in particular in the longitudinal direction of the fibers or sliver, and to at least partially secure them in a direction, in particular perpendicular, to the direction of the high-speed jet, e.g. through the pressure of one or more rollers, and in particular in the region where they are subjected to at least one high-speed jet, to guide them to a surface that extends at an angle of 30° to 90° to the direction of the high-speed jet. The surface has openings thereby, for the removal of the liquid and/or the gas of the high-speed jet, and is designed, in particular, as a grid.

The transport device, guide and/or retention element is designed with particular advantage to rotate and/or turn the fibers between passages through different, in particular two, devices, in particular 180°, and/or the numerous devices for treating the plant fibers retained and/or guided with the at least one guide and/or retention element with at least one high-speed liquid jet or high-speed gas jet are disposed such that they strike the plant fibers retained and/or guided with the at least one guide and/or retention element from different directions, in particular opposing directions, or directions rotated at least 90° about the longitudinal direction of the fibers or sliver, with at least one high-speed liquid jet or high-speed gas jet.

In particular, the device has a device or assembly for the continuous cleaning of at least one device for combing. This can be implemented, for example, by a liquid bath and/or liquid or gas flow, or a liquid or gas jet, which is directed toward the device for combing, such that it removes contaminants trapped therein, in particular, it flushes them out. The device for combing can be formed thereby by rotating rollers, populated with nails, needles, pins, rods and/or rakes, and which are disposed such, and rotate with such a speed, that the nails, needles, pins, rods and/or rakes are guided in a combing manner through the plant fibers, in particular in the form of a sliver.

Further advantages and advantageous embodiments shall be explained in an exemplary manner based on FIG. 3 which shows a treatment strategy for executing the method according to the invention.

A fiber sliver 13 can be seen in FIG. 3, which is formed in the upper left, and is processed, cleaned, stretched and refined in the further course, downward to the right.

A pre-dosing device 36 is shown, which pre-aligns the moist fibers 35, and rinses them over a rise, dosed with a water nozzle 37. Subsequently, the fibers 35 are clamped by a trough intake between a trough 39 and a first roller 11, and removed by a second roller provided with nails, which rotates on its circumference at a speed V2 that is quicker than the first roller rotating at the speed V1. The resulting fiber sliver 13 is then guided over a sieve 14, and treated from above at an angle of 80° with a first high-speed water jet from a first high-speed nozzle 12. The water and released and/or flushed-out components can pass through the sieve 14 into a tank 29 located thereunder. Subsequently, a stretching and combing out of the fiber sliver 13 in a moist state, by a third 14 and fourth 16 clamping roller and a fifth roller 17 provided with nails, which runs at a higher circumferential speed V4 than the circumferential speed V3 of the third and fourth rollers 15, 16, which are synchronized to one another, takes place. As a result, further foreign bodies can be loosened and thus later more easily rinsed out.

The fiber sliver 13 is subsequently guided such that it is exposed at the bottom, and supported toward the top by a second sieve 19. In this position, it is treated by a second high-speed water jet from a second high-speed nozzle 18 at an angle of 80°. The water and released and/or rinsed out components can pass through the second sieve 19, and drop subsequently, or alternatively, into the tank 29 disposed thereunder.

Subsequently, a further stretching and combing-out of the fiber sliver 13 in the moist state takes place, by means of a sixth 20 and seventh 21 clamping roller, and an eighth roller 24 provided with nails, which rotates at a higher circumferential speed V6 than the circumferential speed V5 of the sixth and seventh rollers 20, 21, which are synchronized to one another. As a result, further foreign bodies can also be loosened, and thus later more easily rinsed out.

The fiber sliver 13 is subsequently guided over a third sieve 24, and subsequently treated by a third high-speed water jet form a third high-speed nozzle 23 at an angle of 80°. The water and the released and/or rinsed out components can pass through the third sieve 24, and drop into the tank 29 disposed thereunder.

Subsequently, a further stretching and combing-out takes place in the moist state by means of a ninth 25 and a tenth 26 clamping roller, and an eleventh roller 27 provided with nails, which rotates at a higher circumferential speed V8 than the circumferential speed V7 of the ninth and tenth rollers 25, 26, which are synchronized to one another. The eleventh roller 27 passes downward through the water bath in the tank 29, by means of which it is continuously cleaned.

Subsequently, the fiber sliver 13 is removed and further processed, in this case transferred to a boiler 28.

The circumferential speeds V1, V2, V3, V4, V5, V6, V7, V8 increase respectively from the first roller 10 to the second roller 11, to the third 15 and fourth 16 rollers, to the fifth 17 roller, to the sixth 20 and seventh 21 rollers, to the eight roller 22, to the ninth 25 and tenth 26 rollers, and to the eleventh roller 27.

A method for cleaning and/or increasing the ratio of the fiber length to the fiber thickness of plant fibers (35, 13), characterized in that the plant fibers are treated with at least one high-speed liquid jet (12, 18, 21) or high-speed gas jet, and subsequently combed while moist. The above method, wherein pectin and hemicelluloses of the plant fibers are at least (partially) swollen at the start of the treatment with the high-speed liquid jet or high-speed gas jet. One of the above methods, wherein the plant fibers have a moisture content of at least 25% prior to the start of the treatment with the high-speed liquid jet or high-speed gas jet, or the plant fibers are provided with a moisture content of at least 25%, and are dried prior to the treatment with the high-speed liquid jet or high-speed gas jet to a moisture content of a minimum of 25%. One of the above methods, wherein the plant fibers are treated multiple times with the at least one high-speed liquid jet or high-speed gas jet, and subsequently combed while moist, and/or wherein the plant fibers are treated from two sides with at least one high-speed liquid jet or high-speed gas jet, and subsequently combed while moist.

One of the above methods may include that the plant fibers are stretched while moist.

One of the above methods may include that the liquid of the at least one high-speed jet or high-speed gas jet is removed such that there is no liquid back-up that compromises the high-speed liquid jet or high-speed gas jet, or lays the plant fibers in a liquid bed or allows the plant fibers to float.

One of the above methods may include that the plant fibers contained in a card sliver or card web, or comb sliver are treated with the at least one high-speed liquid jet or high-speed gas jet, and subsequently combed while moist.

One of the above methods may include that the plant fibers are parallelized prior to, after, and/or during the treatment with the at least one high-speed liquid jet or high-speed gas jet, using the at least one high-speed liquid jet or high-speed gas jet and/or at least one alignment high-speed liquid jet or alignment high-speed gas jet.

An application of at least one high-speed liquid jet or high-speed gas jet for cleaning and/or reducing the ratio of the fiber thickness to the fiber length of plant fibers, characterized in that the plant fibers are treated with at least one high-speed liquid jet or high-speed gas jet, and subsequently combed while moist.

A device for cleaning and/or reducing the ratio of the fiber thickness to the fiber length of plant fibers, characterized in that a guide and/or retention element for plant fibers is provided, and a device for treating the plant fibers retained and/or guided by the guide and/or retention element with at least one high-speed liquid jet or high-speed gas jet, and at least one device for combing the plant fibers while moist are provided. 

1. A method for obtaining plant fibers from at least one plant stem or from at least one unit of plant bast separated from wood, with or without cuticula, comprising steps of: breaking down the plant stem or the unit of plant bast, with or without cuticula, through treatment with at least one high-speed liquid jet or high-speed gas jet, and wherein the at least one plant stem or the at least one unit comprising plant bast, with or without cuticula, has a moisture content of at least 25%, or vegetable glues of the plant stem or the unit of plant bast are in a swollen state at a start of the treatment with the high-speed liquid jet or high-speed gas jet.
 2. The method according to claim 1, further comprising: moving the plant stem or the unit and the high-speed liquid jet or high-speed gas jet in relation to one another in the direction of a longitudinal extension of the plant stem with a first speed.
 3. The method according to claim 2, wherein in the step of moving and with reference to the plant stem, the first speed is parallel to a speed component of a second speed of the liquid or gas inside the high-speed liquid jet or high-speed gas jet.
 4. The method according to claim 1, wherein in the step of breaking down, the at least one plant stem has a stem or the unit of bast is from a group of eurosids I or has a length of at least 20 cm.
 5. The method according to claim 1, further comprising a step of: generating the at least one high-speed liquid jet or high-speed gas jet through guiding a liquid volume subjected to at least 15 bar through a nozzle.
 6. The method according to claim 1, wherein the at least one high-speed liquid jet or high-speed gas jet exhibits a second speed of the water in the high-speed liquid jet or high-speed gas jet of more than 20 m/s at a location where the at least one high-speed liquid jet or the high-speed gas jet strikes the plant stem.
 7. The method according to claim 1, wherein the step of treating comprises treating the plant stem or the unit with at least two high-speed liquid jets or high-speed gas jets, the first speeds of which are oriented at an angle of at least 60° relative to each other, or the plant stem or the unit passes at least twice through the at least one high-speed liquid jet or high-speed gas jet, and wherein the plant stem is rotated at least 90° about the plant stem's longitudinal axis between the two passes through the at least one high-speed liquid jet or high-speed gas jet.
 8. The method according to claim 1, further comprising treating the plant stem on at least 180° of the plant stem's circumference by the at least one high-speed liquid jet or high-speed gas jet.
 9. An application of at least one high-speed liquid jet or high-speed gas jet for obtaining plant fibers from at least one plant stem or from at least one unit of plant bast separated from wood, with or without cuticula, wherein the plant stem or the unit of plant bast, with or without cuticula, is broken down through treatment with the at least one high-speed liquid jet or high-speed gas jet, and the at least one plant stem or the at least one unit comprising plant bast, with or without cuticula, has a moisture content of at least 25%, or vegetable glues of the plant stem or the unit of plant bast are in a swollen state before starting the treatment with the high-speed liquid jet or high-speed gas jet.
 10. A device for obtaining plant fibers from at least one plant stem or from at least one unit of plant bast separated from wood, with or without cuticula, comprising: a retention or guide element for at least one plant stem or at least one unit comprising plant bast separated from wood, with or without cuticula; and a device for treating the at least one plant stem or unit comprising plant bast separated from wood received in the retention or guide element with at least one high-speed liquid jet or high-speed gas jet.
 11. The method according to claim 1, wherein the step of breaking down of the plant stem or the unit of plant bast, with or without cuticula, through treatment with at least one high speed liquid jet or high-speed gas jet occurs when vegetable glues of pectin and hemicellulose are in a swollen state at the start of the treatment.
 12. The method according claim 4, wherein in the step of breaking down, the unit of bast is a hemp plant or a nettle plant.
 13. The method according claim 5, wherein the step of generating comprises guiding the liquid volume subjected to at least 30 bar through the nozzle.
 14. The method according claim 5, wherein the step of generating comprises guiding the liquid volume through the nozzle, where the nozzle has a cross sectional tapering by a factor of from about 2 up to about
 20. 15. The method according to claim 6, wherein the exhibited second speed of the water is more than 30 m/s.
 16. The method according to claim 6, wherein the exhibited second speed of the water is more than 50 m/s.
 17. The method according to claim 7, wherein the step of passing the plant stem or the unit through the at least two high-speed liquid jets or high-speed gas jets, comprises orienting the first speeds at at least 90° relative to each other.
 18. The method according to claim 7, wherein the step of passing the plant stem or the unit through the at least two high-speed liquid jets or high-speed gas jets, comprises orienting the first speeds at at least 120° relative to each other.
 19. The method according to claim 7, wherein the plant stem or the unit passes at least twice through the at least one high-speed liquid jet or high-speed gas jet, and wherein the plant stem is rotated through at least 120° about the plant stem's longitudinal axis between the two passes.
 20. The application according to claim 9 wherein vegetable glues of pectin and hemicellulose of the plant stem or the unit of plant bast are in a swollen state before starting the treatment with the high-speed liquid jet or high-speed gas jet. 